The present invention relates generally to devices for obtaining gaseous samples, and particularly to obtaining air samples.
In recent years the attention of the public has increasingly focused on the dangers of air pollution. Along these same lines, the government has established clean air standards which are administered by the Environmental Protection Agency and the Occupational Safety and Health Administration. In order to determine the presence and extent of harmful chemicals and particulate matter in the air, systematic and scientific sampling must be conducted.
One particular area of concern in recent years has been exposure by hospital operating room personnel to commonly used gaseous anesthetics. In order to prevent exposure to excessive levels of such anesthetics, several devices have been developed for sampling the atmosphere in hospital operating rooms. The samples obtained are chemically analyzed in order to determine the extent of such anesthetic contamination. Among such devices are those of Calibrated Instruments, Inc., and Boehringer Laboratories, which utilize a vacuum pump to inject a quantity of air within the operating room into a sample receptacle for later chemical analysis. However, several problems have remained in obtaining samples of operating room air. Primary among these is the fact that an electric pump is required to collect the air samples. The danger of explosion being extremely high in operating rooms due to the flammable nature of the anesthetic gases, such electrical devices must be shock proof, making them extremely expensive. In addition, such vacuum pumps tend to be expensive to operate either in the use of electricity or in batteries.
A recent improvement in atmospheric sampling apparatus may be found in U.S. Pat. No. 4,191,054 assigned to the assignee of the present invention, Air Test Labs, Inc. The aforementioned device utilizes the flow of liquid to create a vacuum thereby drawing atmospheric samples into a container. However, use of such a liquid is contraindicated when testing for water soluble particulate matter contained in the air.
Therefore, it is an object of the present invention to provide an apparatus for obtaining air samples which does not require the use of a moving liquid, which does not require the use of electric motors, and which is inexpensive and easy to use.